The Grey’s Anatomy alum, 49, decided to go see a doctor after noticing differences in herself as she went about her everyday routine. “My pilates instructor said, ‘Hey, your right side is dipping.’ And it didn’t feel like I was off, but I looked down and could see it. Then when I was driving, I started swerving into the right lane,” Walsh told Cosmopolitan in an interview published on Monday, September 18. “The exhaustion got to the point where I could drink five cups of coffee and still not feel awake or clear. And then around April, I started having more cognitive difficulties. It felt like aphasia, but it wasn’t just not being able to find words; I would lose my train of thought, I wasn’t able to finish sentences, and that was when I got really alarmed.”

“I really pushed to see a neurologist, I just had an instinct. I had to really advocate, because they don’t hand out MRIs so easily, but I got an MRI and thank God I did, because it turned out I had a very sizable brain tumor in my left frontal lobe,” she continued. “And three days later I was in surgery having it removed.”

Playing a surgeon on ABC’s Grey’s Anatomy and Private Practice didn’t calm Walsh’s nerves as she headed for the operating room. “You’d think that after playing Dr. Addison for the better part of a decade, where I spent more time on a hospital set than at my house, that I would feel somehow more comfortable,” she explained to Cosmo. “But I was such a little scaredy-cat. In the hospital, I felt like I might as well be six years old. My mother gave me rosary beads, my friend gave me a stuffed animal to go into surgery with.”

Walsh —who is now partnering with Cigna as part of their TV Doctors Campaign alongside former Grey’s costar Patrick Dempsey — added: “I played a real badass on TV, but when it comes to being a patient it’s such a vulnerable experience.”

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